Recently, there have been growing demands for a silver halide photographic light-sensitive material having a higher sensitivity. To improve sensitivity, sensitizing dyes are commonly employed. Of sensitizing dyes, those represented by the following Formulae [I-a] and/or [I-b] gained experts' attraction since they are highly sensitive to a wavelength region of 700 to 800 nm: ##STR2##
However, it has been found that the use of the above sensitizing dye allows the sensitivity of a light-sensitive material to vary by heating or with the passage of time.
As a result of extensive studies, the inventors have found that the above problem can be solved by the use of a compound represented by Formula [II] in combination with the above sensitizing dye. By the combined use of the sensitizing dye represented by Formula [I-a] and/or [I-b] and the compound represented by Formula [II], it is possible not only to improve sensitivity considerably but also to prevent the fluctuation of sensitivity by heating or with the passage of time.